Could fibromyalgia cause pain in the upper back flesh and muscles plus very hot sensation(burning hot especially in the back of head?what causes that?

Yes: Fibromyalgia causes widespread pain in muscles. It is possible that with use, a smaller area of your body has more intense symptoms. Underlying the fibromyalgia you may have arthritis of the cervical spine which increases the possibility of your symptoms. Isolated areas of pain which last over 3 days and do not respond to rest, massage or stretch need to be examined by your physician.